1. Field of the Invention
The present invention relates to a method and apparatus for speed dialing in a mobile communication system. More particularly, the present invention relates to a method and apparatus for performing a speed dial function in the event of receiving an international roaming service or changing a service network by using a speed dial applet that manages speed dialing classified by countries or networks.
2. Description of the Related Art
With development of mobile communication technologies, mobile communication terminals have become greatly popular and are an important if not essential accessory to most people. One convenient feature of a mobile communication terminal is its ability to store information, especially telephone numbers of friends, acquaintances, frequented restaurants and the like. That is, a user is able to store telephone numbers in a memory of a mobile communication terminal in order to more conveniently use the mobile communication terminal by not having to remember so many important numbers. Furthermore, the mobile communication terminal may be provided with a speed dial function. With the speed dial function, the user maps a telephone number, used frequently among the stored telephone numbers, to a speed dial number or code. By having the frequently called telephone number mapped to a speed dial number, the user is able to merely input the speed dial number to place a phone call to the telephone number mapped to the speed dial number. Thus, the user can save time by not having to remember and dial the desired telephone number.
A Subscriber Identity Module (SIM) card is detachably installed in a mobile communication terminal that is based on the Global System for Mobile communications (GSM). Certain information about the user is stored in the SIM card. Therefore, if the SIM card is installed in another mobile communication terminal, for example a mobile terminal that is not owned by the user, the user can still be provided a communication service through the other mobile communication terminal by means of his own telephone number.
A SIM Application Toolkit (SAT) is used to provide an interface between the mobile communication terminal and the SIM card. More specifically, an SAT provides a mechanism for admission of applications and supports a standard SIM toolkit mechanism necessary by the application to enable an interaction with the mobile communication terminal.
FIG. 1 is a diagram illustrating an example of a conventional SIM toolkit mechanism.
Referring to FIG. 1, an SAT is used to allow a SIM card to send commands to the terminal. Through these commands, a user may provide an input and obtain a menu display or an SMS message transmission function. In actuality, a mobile communication terminal operates as a master and a SIM card operates as a slave that receives function requests from the terminal. A corresponding application is stored in the SIM card.
For example, it is assumed that a terminal can connect to a SIM card by a SIM toolkit and the SIM card has a SIM toolkit application installed.
The terminal waits for a command from the SIM card. The SIM card displays a corresponding application list to be selected by a user of the terminal. For example, the SIM card may display information about the weather, information about sports, information about bank businesses, etc. and the terminal's user selects a corresponding application.
Herein, commands operating an SAT are based on the contents specified in the 3GPP TS 11.14 standard which is the specification of the SIM Application Toolkit for the Subscriber Identity Module-Mobile Equipment (SIM-ME) interface. Commands transmitted from the SIM card to the terminal are called proactive commands and commands transmitted from the terminal to the SIM card are called envelope commands. By a combination of such commands, service providers develop their unique services, such as transmission/reception of SMS messages providing specific services and connection of calls by specific service numbers, to provide SIM applications.
As described above, in the case of a conventional SAT function, a service provider implements the SAT function for a specific service in a SIM (i.e., a built-in SAT service), and a user selects an SAT menu to receive a specific service, for example a request for weather information, traffic information and the like, by dialing or by transmitting a text message.
In the case of a conventional speed dial function set in a terminal, a speed dial must be reset in the event of a change to another terminal and only one dialing number (or application) can be registered in one speed dial number.
Also, in the event of an international roaming mode, a speed dial used in a home network cannot be used in a foreign network and must be registered again.
Also, when Global System for Mobile communications (GSM)/Universal Mobile Telecommunications System (UMTS)/Wideband Code Division Multiple Access (WCDMA) schemes are used by multi-mode terminals and various network SIM cards, if a Service Dial Number (SDN) of a specific service network is registered in a speed dial, a corresponding speed dial does not operate in the event of a change to another network.